Inking or distributing roller for thinly liquid inks



July '21, 1959 E. PFRFFLE 2,895,417

INKING 0R DISTRIBUTING ROLLER FOR 'THINLY LIQUID INKS Filed Sept. 25, 1956 United States Patent INKIN G 0R 'DIS'IRIBUTIN G ROLLER FOR THINLY LIQUID INKS Ernst Pfiiifle, Neuffen, Wurttemberg, Germany, assignor to Hans Sickinger, Providence, R.I., an individual Application September 25, 1956, Serial No. 611,895

Claims priority, application Germany November 5, 1955 2 Claims. (Cl. 101-375) The present invention relates to inking or distributing rollers for highly fluid inks such as aniline dyes, to be used for instance in ruling machines. It is an object of the invention to prevent the ink from running off the printing faces on the ruling bars, since this may have certain unfavorable consequences and result in disturbances in the uniformity of work and continuity of operation of such machinery.

In the known devices used in this field, the inking rollers most commonly employed consist of bronzeor rubber-faced rollers having a cylindrical base shell and raised ruling bars for cross ruling the paper. The inks used are as a rule aniline colors which are diluted with water until the thinly liquid or watery state is reached. During operation of conventional high speed ruling equipment, the ink tends to be drawn off the edges of the ruling bar working surfaces onto the base shell of the roller. This occurs mainly at the trailing edges of the ruling bars, that is, the edges located opposite the direction of rotation. During this process, the ink will collect in the form of droplets in various places on the roller base shell and the drops will gradually increase in size until they are thrown through the action of centrifugal force onto the paper being ruled, thus producing splashes or blotches thereon. Furthermore, the ruled lines on finished paper printed with known devices prove to be uneven in strength, Le. a given ruled line may have both thin and thick places. These adverse manifestations are caused by rarefaction of air in the individual chambers formed between the roller base shell and the paper extending over the ruling bars. The rarefaction of air is produced during operation of the machine by eductive action occurring at the two end faces of the inking roller. The currents that occur here during operation draw oli air and produce a partial vacuum, thus causing the ink to flow off gradually from the upper ruling bar faces down their sides onto the roller base shell. This explains why the general direction of ink flow-off is opposite the sense of rotation of the roller.

The aforesaid deficiency could naturally be remedied by increasing the viscosity of ink, for instance by an admixture of glycerin, to such an extent that it would no longer be caused to flow by these pressure differentials. The same result could also be obtained by reducing the machine speed. However, it is a natural aim to operate ruling machines of the well known conventional design at high speeds and even to increase the speeds in order to improve output. Similarly, the use of thinned aniline inks has become a firmly established practice in printing shops for various important reasons, and to replace such inks by thicker ones would not represent a satisfactory remedy.

The present invention corrects the above defects by preventing the rarefaction of air between the roller shell and paper web during operation of the machine. This is accomplished by the provision of radial passages con- 2,895,417 Patented July 21, 1959 ice necting the inner and outer surfaces of the roller shell between the various ruling bars. The presence of these connecting passages results in a pressure compensating effect by means of irregular eddyings in the air spaces between the roller base and the paper which prevent the pressure in these air spaces from being decreased. At the same time, the creation of forces which might cause ink to be drawn from the ruling bar faces is prevented by the presence of these connecting passages.

In the drawings:

Figure 1 is a top view in cross section of an inking roller incorporating the invention, parts being broken y;

Figure 2 is a side view of a portion of the roller, showing the location of the passages; and

Figure 3 is a fragmentary cross-sectional view taken along the line 33 of Figure l and showing the relative positions of a connecting passage and a ruling bar.

The inking roller is formed in known manner of a shaft 1 and two end supports such as disks 2 mounted thereon, over which a roller base shell 3 is drawn and fastened. Over the latter a tube 4, for example of bronze, is snugly drawn to form the outer jacket, the base shell being fabricated of a less expensive material. Tube 4 is provided with a plurality of ruling bars 5 which may differ in spacing and thickness according to individual requirements. It will be noted that the end faces of tubes 4 have spaces 6 between the ends of bars 5 past which air will flow during roller rotation, thus producing the eductive effect discussed above.

Between each pair of adjacent bars 5, the composite roller jacket 3, 4 is provided with one or more radial passages 7 connecting the inner surface of base shell 3 and the outer surface of tube 4. Passages 7 are preferably spaced inwardly from the ends of the roller, and the size of the passages is such that air may flow between the central chamber 8 formed within cylinder 3 and the various individual spaces or channel-shaped depressions 9 (indicated in Figure 3) formed by the outer surface of the base shell and the paper Web lying over ruling bars 5. The paper web is shown by dot-dash lines at 11 in Figure 3. The irregular eddy currents of air between chamber 8 and spaces 9 will prevent a pressure decrease in the latter spaces, thus assuring the retention of ink on the outer faces 12 of ruling bars 5.

While it will be apparent that the preferred embodiment of the invention disclosed is well calculated to fulfill the objects above stated, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the proper scope or fair meaning of the subjoined claims.

What is claimed is:

l. A roller for printing ruled lines comprising a cylirrdrical shell having an inner chamber, a plurality of circumferentially spaced ruling bars raised from the surface of said shell, each pair of adjacent ruling bars forming therebetween a non-inked channel-shaped depression, said ruling bars having surfaces of predetermined width for the reception of ink, and a plurality of passageways connecting said depressions with the inner chamber of said shell, whereby air may flow at all times between the inner chamber of said shell and all the spaces between said bars.

2. A roller for printing ruled lines comprising a shaft, a pair of spaced end supports on said shaft, a cylindrical shell on said end supports having an inner chamber, the entire inner surface of said shell being exposed to said inner chamber, a tube surrounding the outer surface of said shell, a plurality of circumferentially spaced ruling bars raised from the surface of said tube, each pair of w 3 adjacent ruling bars forming therebetween a non-inked References Cited in the file of this patent channel-shaped depression said ruling bars having sur- UNITED STATES PATENTS faces of predetermined wldth for the receptlon of ink, and a plurality of passages-through said shell and tube 948011 Goldsmlth 1 1910 spaced inwardly from said end supports and connecting 5 1,668,322 Kessler May 1928 said depressions with the inner chamber bf said shell, 2621591 Henderson 1952 whereby the air may flow at all times between the inner lchamber of said shell and all the spaces between said FOREIGN PATENTS ruling bars. 649,515 Germany Aug. 26, 1937 

